Page:The Zoologist, 3rd series, vol 1 (1877).djvu/543

Rh stomach which precedes it, and from the rectum which follows it; 4th, the rectum, of which the lining membrane is reddish, communicating with the excretory orifice.

The alimentary canal is quite straight. The heart, like the blood-vessels, is filled with red blood, and the annular swelling—in the middle of which the heart is situated—receives a great number of these vessels. This led Dutrochet to regard it as an organ of respiration, akin to lungs. He could discover no trace of those little pouches which, to the number of nine on each side, are found in the Medicinal Leech, Hirudo medicinalis.

With regard to the habits of Trochetia, Dutrochet stales that it does not live in the water, but on moist soil, where it pursues earthworms, on which it preys, and which it swallows piecemeal (par tronçons). When placed in water he found that it died in three or four days—a statement, however, which has received some modification at the hands of later observers. On the whole Dutrochet considered that the annelid in question constitutes a genus intermediate between the Earthworms and the Leeches, but nearer to the latter than to the former.

The few authors who immediately succeeded Dutrochet in noticing this annelid, as Lamarck and De Blainville, apparently added little or nothing from their own observation to what had previously been made known concerning it. Lamarck corrected Dulrochel's generic name from Trocheta to Trochetia, and after pointing out that the genus is distinguished from Hirudo by having the mouth bilabiate, and possessing neither teeth nor eyes, he gives the following salient characters:—"Body long, cylindrical, anteriorly larger, and somewhat flattened posteriorly, and